by Jean Jacques Nguimbous-Kouoh, Simon Ngos III and Eliezer Manguelle-Dicoum
Original Research
To resolve the problem of gravity mapping in the Mayo-Kani Division, we extracted a sample of data from the high-resolution Bouguer anomaly database EGM2008. The objective of this process was to map and detect subsurface anomalies in the region. Regional-residual separation was applied to the data using a third-order polynomial fit. This separation enables to obtain regional and residual maps. Other filtering actions, such as horizontal and vertical derivatives, have been applied to the data to enhance sources of anomalies in the study area. The residual map of the study area was superimposed on the geological map to delineate and interpret the correlation with the shallow geological structures. The main sources of residual gravity anomalies have been recognized. The interpretation of the derived maps revealed the N-S, E-W, NE-SW and NW-SE structural patterns. These trends have been associated with the major structural directions observed in the Far North Cameroon region. The Euler Deconvolution allowed the detection of sources of anomalies and to determine their depths. The fracture map obtained from this method has improved knowledge on the search for buried ores and the geological structures associated with oil and gas deposits. Overall, the generated gravity maps provided a better understanding of the Mayo-Kani geological setting.
Journal of Geosciences and Geomatics. 2019, 7(1), 42-53. DOI: 10.12691/jgg-7-1-5
Pub. Date: February 27, 2019
12510 Views1892 Downloads
by Quentin Marc Anaba Fotze, Anatole Eugene Djieto Lordon, Joseph Penaye, Jean Paul Sep and Mary Immaculate Neh Fru
Original Research
A geological based remote sensing study was carried out over the Poli group in Garoua (northern Cameroon), renowned for its hydrothermally occurring mineralizations (Gold and Uranium). In this study, Landsat 8 OLI/TIRS coupled with magnetic data were used in order to realize a regional litho-structural mapping of hydrothermal alteration targets, required for mineral exploration. Hence, the enhancement of both Landsat 8 and magnetic data was achieved via digital image processing (DIP) techniques notably Band rationing (BR), Principal Component Analysis (PCA), Horizontal gradient (HG), and lineament extraction algorithms. Based on reference band ratio combinations (Sultan’s and Kaufmann’s) and Crosta Technique (PCA analysis), hydrothermally altered minerals such as hydroxyl-bearing minerals and iron oxides were identified. The PCA map was shown to better illustrate hydrothermally altered areas than Band ratios. Thus, a classification map emphasizing on mineral targets was obtained from the PCA map. Besides, the CET grid analysis tool (horizontal gradient) from Geosoft software 8.4 and the line algorithm (pan band 8) from Geomatica 2013 allowed the extraction of subsurface and surface lineaments respectively. The resulting lineaments showed a predominant E-W trending direction, which suggests a major tectonic event having prevailed within the area. Other directions include NE-SW/ENE-WSW, and N-S. The generation of a target exploration map, via ArcGIS 10.4.1, was performed by the overlay of hydrothermal alteration mapping and structural mapping. New regional maps, providing a useful insight for further mining exploration, were obtained.
Journal of Geosciences and Geomatics. 2019, 7(1), 28-41. DOI: 10.12691/jgg-7-1-4
Pub. Date: February 09, 2019
19566 Views2289 Downloads
by Jacques Wassouo Wadjou, Abakar Mahamat, Fodoué Yaya, Ethel Ashukem Nkongho, Eugene Pascal Binam Mandeng, Dagwai Nguihdama and Ismaela Ngounounou
Original Research
The Bindiba gold district study in the East Cameroon region was done using a combination of Landsat 8 ETM image processing techniques, SRTM imagery and fieldwork. The various digital processing methods of treatment applied such as color compositions and component analysis showed lithological differentiation of the different formations of the study area. Directional filtering and treatments such as the Sobel have made a good linear mapping where we have been able to list more than 293 lineaments in which two types have been distinguished. The type I lineaments or penetrative lineaments correspond to schistosity trajectories. This interpretation is confirmed from field data which revealed schistosity plans mainly oriented NE-SW. Type II lineaments or non-penetrative lineaments are characterized by greater cartographic continuity and lesser spatial density. These lineaments thus represent the fracturing of the study area. The results of this lithology and linearization mapping, based on the superposition of the different images from the treatments and the field data, made it possible to identify the zones favorable for gold concentration and highlighted two gold mineralization corridors. This is the N30-35E steering corridor and the N110-135E steering corridor.
Journal of Geosciences and Geomatics. 2019, 7(1), 15-27. DOI: 10.12691/jgg-7-1-3
Pub. Date: February 02, 2019
15476 Views2093 Downloads1 Likes
by I.A Kwami, J.M Ishaku, Y.S Hamza, A.M Bello and S. Mukkafa
Original Research
A total of 50 groundwater samples were collected from Hand dug Wells and Bore holes in Gombe area and environs and were analyzed for their physio-chemical characteristics aimed at interpreting the groundwater quality. Multivariate statistical methods, namely: the hierarchical cluster analysis (HCA), and the principal component analysis (PCA) were used to study the spatial variations of the most significant water quality variables and to determine the dominant processes affecting the water quality. Principal Component Analysis (PCA) on the data indicates three factors which explain about 61.004% of the total variance, and suggests temporary hardness of water, salinity of the groundwater and dissolution of bedrock material as the dominant processes affecting the water quality in the study area. Whereas hierarchical cluster analysis HCA indicate two clusters, and suggests salinity of the groundwater, natural mineralization, bedrock dissolution, Temporary Hardness and anthropogenic contamination as the dominant processes affecting the water quality parameters in the study area.
Journal of Geosciences and Geomatics. 2019, 7(1), 9-14. DOI: 10.12691/jgg-7-1-2
Pub. Date: January 21, 2019
7229 Views1447 Downloads1 Likes
by Barnabas Morakinyo and Kehinde Sunmonu
Original Research
This research examines the consistency of the value of tidal datum obtained for Nwaniba River in Akwa Ibom State of the Niger Delta (Nigeria). Two sets of tidal data from 10/05/2007-10/06/2007 and 10/05/2017-10/06/2017 observed three times a day (Morning: 7: 30-9: 30; afternoon: 12: 00-14: 00 and evening: 16: 00-18: 00) at every 2 minutes interval were considered in order to evaluate a trend. Mean Highest Water Level (MHWL), Mean Lowest Water Level (MLWL) and Mean Water Level (MWL) for the three times per day were computed. The weekly MHWL and MLWL for each of the 5 week; average MHWL and MLWL for the 5 weeks were also computed. The water level measured within (10/05/2017-10/06/2017) is higher than that of (10/05/2007-10/06/2007) except in few cases. The highest (149.000 cm) and lowest (1.80 cm) water levels for 2007 observation were recorded on 08/06/2007 at (08: 40) and on 10/05/2007 at (7: 46) and 23/05/2007 at (8: 28) respectively; while the highest (152.300 cm) and lowest (1.801 cm) water levels for 2017 observation were recorded on 15/05/2017 at (07: 53) and on 27/05/2017 at (9: 08) and on 08/06/2017 at (08: 32) respectively. The observed Lowest Water Level (LWL) of 1.800 cm was adopted as the tidal datum for Nwaniba River in 2007. The observed LWL for 2017 is 1.801 cm; and the difference between the 2017 LWL and 2007 LWL which is (δLWL) is 0.001 cm. The value of (δLWL) = 0.001 cm shows that the value of LWL of 1.800 cm adopted in 2007 as the tidal datum still remains consistent when compared to the observed LWL of 1.801 cm for 2017 observations. Based on the LWL obtained for 2007 and 2017, it can be concluded that the tidal datum for Nwaniba River is consistent from 2007 to 2017. Also, based on the difference between average MWL for 2007 and 2017 = (δMWL) = 1.247 cm, it can be concluded that the water level at Nwaniba River has increased with 1.247 cm for the period of observation. In addition, the range of values of R2obtained is 0.000-0.046 i.e. 5 %, which shows that only 5 % of the variation in MHWL and MLWL can only be attributed to the variation in time.
Journal of Geosciences and Geomatics. 2019, 7(1), 1-8. DOI: 10.12691/jgg-7-1-1
Pub. Date: January 15, 2019
7335 Views1141 Downloads